Harnessing speckle for a sub-femtometre resolved broadband wavemeter and laser stabilization
Abstract
The accurate determination and control of the wavelength of light is fundamental to many fields of science. Speckle patterns resulting from the interference of multiple reflections in disordered media are well-known to scramble the information content of light by complex but linear processes. However, these patterns are, in fact, exceptionally rich in information about the illuminating source. We use a fibre-coupled integrating sphere to generate wavelength-dependent speckle patterns, in combination with algorithms based on the transmission matrix method and principal component analysis, to realize a broadband and sensitive wavemeter. We demonstrate sub-femtometre wavelength resolution at a centre wavelength of 780 nm, and a broad calibrated measurement range from 488 to 1,064 nm. This compares favourably to the performance of conventional wavemeters. Using this speckle wavemeter as part of a feedback loop, we stabilize a 780 nm diode laser to achieve a linewidth better than 1 MHz.
Citation
Metzger , N K , Spesyvtsev , R , Bruce , G D , Miller , B , Maker , G T , Malcolm , G , Mazilu , M & Dholakia , K 2017 , ' Harnessing speckle for a sub-femtometre resolved broadband wavemeter and laser stabilization ' , Nature Communications , vol. 8 , 15610 . https://doi.org/10.1038/ncomms15610
Publication
Nature Communications
Status
Peer reviewed
ISSN
2041-1723Type
Journal article
Description
We acknowledge funding from EPSRC through an Impact Acceleration Account (IAA) Case Study award and grants EP/J01771X/1 and EP/M000869/1.Collections
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